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Chapter
5: "We're not in Kansas anymore!"
"...No
master mariner dares to use it least he should be suspected of being
a magician; nor would the sailors venture to go to sea under the command
of a man using an instrument which so much appeared to be under the
influence of the powers below." Guiot of Provins ca 1205 A.D.
The Exxon
Valdez left harbor on March 23, 1989, and within hours unleashed an
ecological catastrophe as it ran aground on Bligh Reef; 12:04 AM on
March 24. The spilling of 11 million gallons of oil triggered a $5.3
billion lawsuit in a highly publicized court case. A decade later, the
damage to the Prince Williams Sound is still evident if you literally
scratch the surface of the ecosystem. The investigation focussed on
the circumstances leading up to the grounding, the absence of the Captain
from the Bridge, and the failure of the Third Mate to follow a proper
course, but there may have been other factors at work as well.
The powerful
geomagnetic storm that triggered the Ontario Blackout on March 13 was
not the only event that rocked the magnetosphere that month. Ten days
later, a secondary storm began 14 hours before the Exxon Valdez ran
aground. The IMP-8 research satellite recorded a powerful surge of high-energy
electrons and protons lasting 24 hours. Meanwhile, images from the Dynamics
Explorer Satellite showed a bright crown of aurora girding the north
polar zone, especially in the nighttime sector that included Canada
and Alaska. Had the skies been clear over Valdez Harbor on March 24,
sky watchers would have seen a marvelous Northern Lights display.
The displays,
by themselves, have little consequence for navigation, but they do signal
that powerful currents of electrons are flowing in the upper atmosphere,
and these electrojet currents make themselves felt, magnetically, on
the ground. Magnetic field data from middle-latitude observatories traced
significant changes in the vertical component of the geomagnetic field.
The ‘Dst’ storm-time index, like a barometric reading, pitched up and
down between March 22 - 25 as ionospheric currents flowed strongly,
but erratically, and reduced the Earth’s field by up to 1% vertically.
Meanwhile, magnetic observatories at Sitka, Barrow and College, Alaska,
recorded up to one-degree changes in the direction of magnetic north.
The Exxon Valdez ran aground in the middle of one of these magnetic
excursions that occurred between 11:00 PM on March 23, and 12:30 AM
on March 24.
After leaving
the harbor, the Exxon Valdez like other ships ahead of it, had to navigate
through a narrowing of the channel. The Columbia Glacier ice flows had
calved many icebergs, and these were now flowing into the channel constricting
it to a narrow, 1,500-yard wide passage near Bligh Island. Records show
that the Exxon Valdez made a bearing change of 180 degrees at 11:39
on March 23 which was to be followed on autopilot for four miles before
coming around the edge of an ice flow. Although there was no magnetic
observatory at Valdez, and the nearest ones were at Sitka and College
Alaska located hundreds of miles away, the magnetic conditions sensed
by the three observatories were about the same. A magnetic compass on
the Exxon Valdez would have detected up to 0.3 degree deviations from
the intended bearing, which over a four mile run would have added up
to 100 feet or so of deviation near the end of the run at Bligh Reef.
This is only about 1/9 the length of the tanker. A second course change
was planned at the end of the four mile leg, and it is this one which
came seven minutes too late. Because of the delay, the tanker overshot
the narrow slot between the ice flow and the reef, and the rest is history.
Two other ships, the Brooklyn and the Arco Juneau, had navigated this
channel between 10:47 AM and 7:22 PM on March 23 with no difficulty,
and an even larger magnetic storm was in progress between 5:50 PM and
6:30 PM on that day, with deflections up to one degree.
The Exxon
Valdez navigation aids rely on Loran-C and not magnetic compass bearings.
This incident, then, seems to be a spectacular case where a solar storm
was in progress with large magnetic swings, and a ship navigating a
narrow channel was grounded, but the two events were apparently unrelated.
The initial expectation that we had of cause and effect was based on
the very logical premise that geomagnetic storms cause significant deviations
in compass bearings. However, if no magnetic compass is used, then there
can be no navigation impact even by a major magnetic storm. If the Exxon
Valdez was immune from direct magnetic disruptions, could the Loran-C
system have been affected instead?
For this
to be a viable possibility, the storm-time conditions would have to
produce significant propagation delays in the short-wave Loran-C navigation
beacons that were used to figure bearings between 11:30 PM and 12:30
AM. The reports on the events leading up to the grounding indicate that
there were frequent radar interruptions noted at the time that the Exxon
Valdez left harbor. The ‘blip’ representing the ship apparently faded
in and out of detectability as the ship passed Rocky Point, located
just outside the Valdez Narrows harbor entrance. Although one might
initially attribute this to the effects of the storm, the actual explanation
is more mundane.
This radar
problem was well-known to the operators at the Valdez Coast Guard Station,
and of itself, not a condition that had to do with solar storms. It
was simply another example of not having a second radar station located
near the mouth of the harbor to extend the range of the main installation
at Valdez. Moreover, the Third Mate had tested the navigation equipment
at 7:24 PM before leaving the harbor, and this check apparently included
the ship’s radar, gyrocompass, automatic pilot and course indicator.
Nothing out of the ordinary was discovered. One would expect that a
storm-time process capable of significantly affecting navigation would
have showed up three hours before the grounding, and at a time when
the geomagnetic disturbances were even stronger.
So we come
up empty handed. Even though a cursory examination of the Exxon Valdez
grounding seemed to turn up an exciting new ‘smoking gun’ for a very
spectacular shipwreck, there appears to be no cause-and-effect link
between the key events. Had the Exxon Valdez’s navigation been affected
by one degree errors in plotting a course and following it, the several
hundred feet uncertainty near Bligh Reef, would have initially made
a difference, but it wouldn’t have avoided the inevitable impact. With
a ship traveling at 20 feet per second, it would have just delayed the
inevitable by a few more seconds.
We are fortunate
to be living on a planet which has a well-defined magnetic field, and
which has served us as a navigation reference for millennia. Had the
situation been otherwise, ancient mariners may have had to steer their
daytime courses using only nighttime stars as a guide. No one really
knows exactly when the first person came up with the idea of using a
rock to tell direction. It's hard to imagine the trial-and-error process
that could have led up to this discovery. But the history books are
pretty clear that many thousands of years ago some nameless soul discovered
that a particular kind of rock we now call lodestone (magnetite) does
the trick.
The story
seems to begin in ancient China, when Emperor Hoang-ti's troops were
in hot pursuit of Prince Tcheyeou in 2637 B.C. for reasons that are
now lost to us. Ancient Chinese politics is a complex and ever-changing
arena that is mostly inscrutable to the Western mind. The troops eventually
lost their way in a heavy fog, so the Emperor constructed a chariot
upon which stood a figure that always pointed south no matter how the
chariot was pointed. Nearly two millennia later, the Phoenician sage
Sanconiathon wrote, '...It was the God, Ouranos, who devised Betulae,
contriving stones that moved as having life...'., and even Homer
about 900 BC got into the act by mentioning this wondrous technology
in the Odyssey,
'...In wondrous
ships instinct with mind
No helm secures
their course, no pilot guides
Like man
intelligent, they plough the sea
Though clouds
and darkness veil th' encumbered sky
Fearless
thro' darkness and thru' clouds they fly...'
During the
last thousand years, the 'secret weapon' of the Vikings evolved into
the familiar magnetic compass that every Boy Scout and ocean navigator
relies on to see them to safe harbor. We don't need lodestone anymore.
A simple needle balanced midway between its ends suffices to point in
a fixed direction. By the 1600, William Gilbert, the personal physician
to Queen Elizabeth, even wrote a book about how the Earth is one giant
magnet with distinct north and south poles. But over the course of decades
and centuries, navigators discovered that these bearings don't always
run true.
We are living
at a time in the history of the Earth when the magnetic north-south
field is very nearly aligned with the axis about which the Earth spins
each day. We don't know exactly how the Earth does this trick. Geophysicists
think that the 'geomagnetic field' is generated near the hot, electrically
active, core of the Earth where hundred mile wide currents of molten
nickel flow along the equator. Like many rivers of water on the surface
of the Earth, these subterranean currents are not steady, either in
space or time. Over thousands of years, even near the core of the Earth,
things tend to slosh about a bit. If you were standing at the magnetic
north pole, you would soon discover that it moves a hundred yards a
day, and this forces compass navigators to buy new maps every ten years
or so. Map makers and sellers since the 18th century enjoy this aspect
of geophysics quite a bit, and over time actually turn a profit from
it. There are other less predictable changes that occur with magnetic
bearings if you have the patience to look for them.
In the early
19th Century, Baron Alexander von Humbolt, was one of those intrepid
and world-renowned explorers who outfitted expeditions to Africa and
elsewhere to catalog rare plants and animals. His popular stature was
a combination of the measured studiousness of astronomer Carl Sagan
and the down-and-dirty enthusiasm of Titanic discoverer Jim Ballard.
In fact, the London Times regularly published Humbolt's weekly letters
from distant lands and jungles, detailing his on-going exploits. On
one of his years off from studying wild and exotic fauna and flora,
his interests turned to earlier reports that compass needles didn't
always point in the same direction from moment to moment. He and an
assistant decided to look into this behavior a bit more.
With a microscope,
they made around the clock measurements of a compass needle's direction
every half-hour for over a year. What they uncovered were the usual,
and sudden, erratic swings produced by lightning storms, but every once
and a while other mysterious disturbances set their needle gyrating.
It didn't take long for them to realize that the strongest of these
'magnetic storms' always seemed to happen when the Northern Lights could
be seen dancing outside their window or in neighboring lands to England.
This behavior was taken very seriously at the time, because in terms
of our monetary system today, billions of dollars of commerce were at
the mercy of ships steered by magnetic compass. Within a few years,
Humbolt had dozens of 'magnetic observatories' across the globe, were
hard at work measuring compass needle gyrations and magnetic storms.
Magnetic
storms are not something to trifle with. If you are a navigator, they
can cause compass bearing errors as large as several degrees, so that
for up to a full day, your bearings are completely unreliable and you
might not even realize it. This is especially challenging and fraught
with certain catastrophe if you are trying to get through a tight channel
in the dark or in inclement weather. The most dramatic impact of geomagnetic
storms would be a shipwreck or a plane crashing into a mountainside.
Few recorded instances of such tragic events are known, however, there
are stories about a ship that ran aground on Bear Island just before
World War II, and airplane pilots in Alaska have claimed that some crashes
were caused by just such geomagnetic storms. The problem is that historical
accounts of geomagnetically-induced navigation problems are almost entirely
anecdotal. The earliest account is reported in the American Journal
of Science and Arts by a contributor named, simply, 'A. de la Riva',
"M.
de Tessan cites an observation made in 1818 by M. Baral, another French
naval officer, on the same coasts of New Holland, who found that he
had been making a wrong course from following his needle...But on the
evening of the same day, there was a brilliant aurora, and to this he
attributes the deviation,"
In addition
to the many exciting changes in communication technology during the
last 100 years, even the magnetic compass was eventually eclipsed. Navigation
could now be provided by a series of strategically placed transmitters
that ships and planes could lock onto. Within a few years, the LOng
Range Aid to Navigation (Loran) system had all but replaced navigation
by stars and compass, although these might be used occasionally as back-up
aids. Loran coverage was extended over combat areas and along Pacific
supply lines so that by the end of World War II, about 30% of the Earth's
surface had been covered by Loran. The system appeared to be resistant
to geomagnetic storms, but they did have their weakness.
Loran short-wave
signals could be affected by severe static, and to get a reliable and
accurate bearing, you need to measure the arrival times of the signals
from three stations. Because these signals have to bounce off the ionosphere
to get to you, any changes in the ionosphere cause erratic increases
or decreases in the signal's travel time to your ship. This causes course
errors just as surely as if you had been using a magnetic compass. For
instance, during the March 13, 1989 solar storm activity, a shock wave
collided with the Earth's magnetosphere. The ionosphere was severely
affected by this major storm, and a number or reports describe how this
caused Loran navigation signals to become unreliable for several hours.
Since the early 1990's, a new navigation technology has swept the scene:
satellites. The Department of Defense launched 24 satellites to make
up their Global Positioning System. Now, with a handset no bigger than
a cellular telephone, you can find your instantaneous longitude and
latitude no matter where you are on Earth, or in orbit. Between five
and eight of the satellites are above your horizon at any time, and
your hand set receives their timing signals. A computer chip inside
uses the timing information to triangulate your position to within a
few hundred feet or less. Even so, slight changes in the ionosphere
caused by solar storms, add minuscule delays into these signals and
cause position estimates to vary by hundreds of yards.
What was
also maddening about these ionospheric problems was that the solar flares
that triggered them didn't always coincide with geomagnetic or auroral
events. They sometimes happened during broad daylight. When a flare
happens on the surface of the Sun, less than nine minutes later a powerful
burst of X-ray and gamma ray radiation arrives at the Earth, followed
an hour or so later by high-speed energetic particles. This 'one two
punch' of matter and energy plays havoc with the daytime ionosphere,
and causes short-wave dropouts and radio navigation problems that can
last for hours. Solar flares and geomagnetic storms are common enough,
and navigation difficulties are frequent enough, that sometimes the
two are conjoined in time to paint a provocative picture.
During the
March storm in 1989, the New York Times, and many other newspapers,
reported a military helicopter crash near Tucson, Arizona killing
15 people on March 12. It was a moonless night and the pilot was using
night vision goggles to navigate their helicopter. The Air Force had
flown many missions in this way and it was never cited as a contributing
factor in any previous crash. Could this have been a navigation problem
caused by geomagnetic disturbances which later caused the Quebec blackout
a day later? Investigations of the crash turned up the entirely plausible
conclusion that there may have been too little ambient light for the
goggles to properly work. The pilot was literally flying blind.
On March
11, 1989 at 1:10 PM, Air Canada Flight 1363 crashed soon after takeoff
killing 69 people during a snowstorm with 1/2-mile visibility. Could
this have been caused by navigation problems? Again the answer
is no. Investigators concluded that the plane had been over loaded and
that pilot error was to blame for the tragedy. This crash, by the way,
was the major news story in Canada during the entire March 1989 solar
storm episode, and displaced the Quebec blackout to page 3 in the Toronto
Sun newspaper.
During the
February 9, 1907 Great Aurora, the New York Times reported in
an article 'Liners in Collision" that Atlantic Transport liner Menominae
from Antwerp was struck off Beachy Head on the evening of February 9
by the French steamer President Leroy Lallier. The steamer was observed
to move erratically in course before collision. During another severe
Great Aurora on February 24, 1956 the paper announced that six planes
with 16 missionaries on board was reported mission. The planes had left
Cuba enroute to the neighboring island of Jamaica at 2:00 PM but had
never arrived some four hours later. There were no clouds or storms
in the area.
These examples
show rather dramatically why it is so important to study specific events
carefully before jumping to the conclusion that one caused or facilitated
the other. It is not sufficient to merely note a coincidence in time,
and a suspected pathway of impact. Shipwrecks and crashes happen all
the time. The odds are very good that they will happen during geomagnetic
disturbances that, at some level, are also rather common during any
given year. It's just a matter of the odds catching up with you every
once in a while.
Magnetic
compasses are not the only things that seem to need the magnetic field
as a stable reference in time and space. There are many other 'systems'
on the Earth that need to sense their direction to get to food, shelter,
or simply to maintain equilibrium in a thousand other ways. The geomagnetic
field is so subtle you can't feel its presence outright. But somehow,
over millions of years, it seems that organic evolution has managed
to detect this force by trial and error, and incorporate it into the
guidance systems of everything from bacteria to sharks. Even the common
Monarch butterfly relies on a magnetic sense to orient itself on its
annual southward migration to Mexico. Nature, it seems, has also found
other peculiar uses for magnetite, causing a variety of different cells
to stockpile it for other murky purposes than navigation.
Back in
1974, Richard Blakemore and Richard Frankel at the University of New
Hampshire uncovered a remarkable trick that certain kinds of fresh water
bacteria seemed to share. As they grow to maturity, each of them creates
within their single-celled bodies nearly two-dozen pure cubical crystals
of magnetite. Like pearls on a string, the crystals are oriented with
the long axis of the bacterium. One can imagine by some evolutionary
process, primitive organisms somehow grew a single crystal of magnetite,
perhaps as an annoying byproduct of eating. As these crystal wastes
accumulated, the host became more efficient in finding its way to new
locations rather than spinning around and around in the dark. Whatever
the process, lowly bacteria managed to beat humans to the discovery
of the magnetic compass by, oh, about 3 billion years!
Using magnetite
as a clue, scientists have thrown many different organisms under the
microscope, and many have now been found to have at least some kind
of magnetite embedded in them including homing pigeons, tuna, honey
bees, dolphins, whales, green turtles, and Elvis Presley. Richard Frankel
at the Massachusetts Institute of Technology has gone so far as to herald
these discoveries as "the beginning of a new chapter in the story
of the interaction of the biosphere with the geomagnetic field".
They may have jumped the gun a bit.
The story
has become legendary about how homing-pigeon rallies are not held during
times when geomagnetic conditions are unstable. Since 1980, studies
seem to show that pigeons placed blindfolded in a pen and allowed to
move, tend to move most often in the direction of magnetic north. No
single pigeon has been found to do this, but only large numbers of repeated
trials seem to turn up this 'behavior'. Very recently, magnetite has
been found in certain anatomical features of the heads of pigeons called
ethmoid cavity which at least looks like a potent argument that they
have the hardware needed to fashion a magnetic compass. Although some
investigators seem excited by this evidence, others are not as convinced
that pigeons use the magnetic field at all. Also in 1998, thousands
of pigeons suddenly disappeared during an East Coast race. Some were
later recovered in distant farms in Ohio. There was not much of a magnetic
storm going on at this time. Perhaps the pigeons suffered a mild head
cold or some other malady that spread rapidly through the flock. We
will never know for certain what caused this race to be routed so mysteriously.
But apart
from the controversy over pigeon navigation, how, exactly, does an organism
'sense' which direction magnetite crystals are pointing inside them?
How do you know which way a dollar bill is oriented in your pocket?
For the magnetotaxic bacteria, the magnetic field of the Earth acts
on the magnetite crystals to actually turn them into the correct orientation.
Bacteria are so light that even dead ones align with magnetic north
like the arrow of a compass. Larger organisms, however, are much too
big to be physically moved in this way. They have to have some internal
'magnetic sense' that they can recognize, much as we can sense our body
orientation thanks to the semi-circular canals in our middle ear.
The way
some organisms might sense their magnetic surroundings seems to have
been discovered since 1978. Microscopic examination of the magnetite
crystals detected inside animals as diverse as rodents and humans turned
up nervous tissue surrounding these nodules. That many of these organisms
seem to be literally 'led by the nose' is suggested by the fact that
the magnetite concentrations in dolphins, whales, tuna and marlin, are
found in the ethmoid cavity, located where the bones of the walls and
septum of the nasal cavity join. Are humans left out of this exciting
new gold rush of evidence for a new hidden sixth sense? Apparently not.
Since magnetotaxic organisms were discovered, researchers have also
found traces of magnetite in human sinuses in much the same anatomical
location as for other large animals.
Searching
for a magnetite compass among the billions of cells in an organism is
far worse that searching for a magnetic needle in an organic haystack.
Also, just because you find magnetite, (a not especially rare oxide
of iron), inside an organism may not make it a workable compass. There
are reasons why organisms accumulate magnetite that may have nothing
to do with navigation. For instance, clumps of magnetite produce very
powerful local magnetic fields that are known to modify chemical reactions.
Some researchers suggest that nature has just discovered another odd
way to catalyze biochemical reaction in certain kinds of cells. To be
a good compass, magnetite has to be in the shape of a needle or some
other elongated structure. A symmetric nodule simply won't do. In some
organisms that contain magnetite, however, there is no good evidence
that magnetite is aligned in this way. For instance, in one human brain
cell out of about 50,000, magnetite seems to be clumped but not into
long linear chains as they are in bacteria that use them for guidance.
Also these 'magnetocytes', as Joseph Kirchvink at CalTech calls them,
contain magnetite clumps surrounded by "lipid bilayer membranes...containing
several hundred distinct proteins of unknown function". According to
Kirchvink,
"They
are definitely not used to detect the geomagnetic field as they do not
contain linear chains of crystallographically aligned magnetite crystals
as do magnetotactic bacteria, protozoans, migratory fish and birds.
At the risk of engaging in speculation, our best guess is that the magnetite
crystals are important for biochemistry"
One intriguing
possibility is that, instead of being biochemically important, the magnetite
found dispersed in brain tissue may act in some bioelectric fashion.
We have all heard that the brain has a complex electromagnetic 'hum'
with many different cycles going on all at once: Alpha waves, Beta waves
etc. An entire 'biofeedback' industry has grown up in the last 20 years
to help you modify your brainwaves to make you feel better...at least
so the claims say. Curiously, many of these cycles are matched in frequency
by far more powerful rhythmic changes in the environmental geomagnetic
fields. If human brain tissue contains magnetite, but not in a form
that can work as a magnetic compass, could it still act in some way
to operate as a 'psychic compass'? The evidence seems to suggest that
these magnetosomes act to catalyze unknown chemical reactions throughout
the brain. We also know that imbalances of neurotransmitters throughout
the brain have profound impacts on our modes and other mental states.
Could the two be related?
We all know
that there are 'Lies, damn lies, and statistics', but in one curious
study, statistical evidence seemed to show that the admissions to mental
hospitals in New York correlated with what the space physicists call
the geomagnetic Kp index. It is a measure of how unsettled the geomagnetic
field is over the whole planet during a three-hour period. Another study
found a similar correlation with the auroral Ap index (related to the
Kp index) in the psychotic outbursts of patients in a Moscow mental
institution. Soviet researchers Novikova and Ryvkin in 1977 reported
a correlation of geomagnetic events with the number of heart attacks
in Sverdlovsk based on 300 cases. Even deaths from cardiovascular disease
seemed more likely to occur within a day of a geomagnetic storm, as
do convulsive seizures and reports of hallucinations. In 1995, Juan
Roederer at the Geophysical Institute of the University of Alaska in
Fairbanks, summarized many of these medical studies in an American
Geophysical Union article, Are magnetic storms hazardous to your
health?. Taken together, they did seem to show that something very
odd was going on, and he felt it would be a very good idea to look into
them more carefully.
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